Fig. 3

Mean pulmonary arterial pressure (mPAP), peak inspiratory airway pressure (PIP), and RV/ (LV + S) ratio. a mPAP. b PIP. c right ventricular weight (RV)/left ventricular plus septal weight (LV + S) ratio (RV/[LV + S] ratio), an estimate of right ventricular hypertrophy. MCT2: rats at 2 weeks after monocrotaline injection; MCT3: rats at 3 weeks after monocrotaline injection; LV: low tidal volume (6 mL/kg); HV: high tidal volume (35 mL/kg); Baseline: immediately after the assignment of experimental tidal volume; 0.5, 1, 1.5, and 2 h: time after assignment of experimental tidal volume (6 or 35 mL/kg); −0 h (6 mL) (b): PIP before the assignment of experimental tidal volume while all rats were ventilated with a tidal volume of 6 mL/kg; + 2 h (6 mL) (b): PIP when returning to 6 mL/kg from 35 mL/kg after the end of 2-h ventilation. Bars indicate mean ± standard error. n = number of rats